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      <a id="lfo"></a>
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      <a id="Indexlfo" class="indexterm"></a>
      <div class="refnamediv">
        <h2>
          <span class="refentrytitle">lfo</span>
        </h2>
        <p>lfo — 
      A low frequency oscillator of various shapes.
          </p>
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      <div class="refsect1">
        <a id="idp118594416"></a>
        <h2>Description</h2>
        <p>
      A low frequency oscillator of various shapes.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp118595696"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">kres <span class="command"><strong>lfo</strong></span> kamp, kcps [, itype]</pre>
        <pre class="synopsis">ares <span class="command"><strong>lfo</strong></span> kamp, kcps [, itype]</pre>
      </div>
      <div class="refsect1">
        <a id="idp118599168"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>itype</em></span> (optional, default=0) -- determine the waveform of the oscillator. Default is 0.
      </p>
        <div class="itemizedlist">
          <ul class="itemizedlist" style="list-style-type: disc; ">
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 0 - sine</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 1 - triangles</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 2 - square (bipolar)</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 3 - square (unipolar)</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 4 - saw-tooth</p>
            </li>
            <li class="listitem">
              <p><span class="emphasis"><em>itype</em></span> = 5 - saw-tooth(down)</p>
            </li>
          </ul>
        </div>
        <p>
    </p>
        <p>
      The sine wave is implemented as a 4096 table and linear interpolation. The others are calculated.
    </p>
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      <div class="refsect1">
        <a id="idp118608736"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>kamp</em></span> -- amplitude of output
    </p>
        <p>
      <span class="emphasis"><em>kcps</em></span> -- frequency of oscillator
    </p>
      </div>
      <div class="refsect1">
        <a id="idp118611360"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the lfo opcode. It uses the file <a class="ulink" href="examples/lfo.csd" target="_top"><em class="citetitle">lfo.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp118613136"></a>
          <p class="title">
            <strong>Example 417. Example of the lfo opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac      <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o lfo.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1

kcps  <span class="op">=</span> 5
itype <span class="op">=</span> p4	<span class="comment">;lfo type</span>

klfo <span class="opc">line</span> 0, p3, 20
al   <span class="opc">lfo</span> klfo, kcps, itype
asig <span class="opc">poscil</span> .5, 220<span class="op">+</span>al, 1
     <span class="opc">outs</span> asig, asig

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="comment">; sine wave.</span>
<span class="stamnt">f</span> 1 0 32768 10 1

<span class="stamnt">i</span> 1 0 3 0	<span class="comment">;lfo = sine</span>
<span class="stamnt">i</span> 1 + 3 2	<span class="comment">;lfo = square</span>
<span class="stamnt">i</span> 1 + 3 5	<span class="comment">;lfo = saw-tooth down</span>
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        </div>
        <p><br class="example-break" />
    </p>
      </div>
      <div class="refsect1">
        <a id="idp118617392"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: John ffitch</td>
          </tr>
          <tr>
            <td>University of Bath/Codemist Ltd.</td>
          </tr>
          <tr>
            <td>Bath, UK</td>
          </tr>
          <tr>
            <td>November 1998</td>
          </tr>
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        <p>
    </p>
        <p>New in Csound version 3.491</p>
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